During his rule Gimli, son of Glóin, led a number of Dwarves south to Aglarond, where a new Kingdom was settled. Also during his rule mining for mithril in Moria slowly began again, although Moria was not yet permanently settled.

Thorin III had an heir, (or possibly a later descendant) who was held to be the reincarnation of Durin the Deathless, and who succeeded him at his death as Durin VII the Last.